Stepper Motor

COPYRIGHT 1996 E-LAB Digital Engineering, Inc. All rights reserved.

EDE1200 Unipolar Stepper Motor IC

1 = 'STEP' mode, 0 = 'RUN' mode

Speed Control (LSB)

Speed Control

Speed Control (MSB)

Connect to +5V DC

Oscillator Connection

Oscillator Connection

Phase One Drive Signal

Phase Two Drive SignalPhase Three Drive Signal

Phase Four Drive Signal

Connect to +5V DC

Connect to +5V DC

Digital Ground

0 = Disable Motor Drivers

1 = Clockwise, 0 = Counter-Clockwise

1 = Normal Stepping, 0 = Half-Stepping

Single-Step on Falling Edge in 'STEP' mode

EDE1200Out 3

Out 4

+5V

+5V

GND

Free Spin

Direction

Half-Stepping

Step Run

A

B

C

+5V

OSC2

OSC1

Out 1

Out 21

2

3

4

5

6

7

8

9 10

11

12

13

14

15

16

17

18

The EDE1200 Unipolar Stepper Motor IC is a 5 volt, 18 pin package designed to interface a logic-level input byte to a stepper motor. The EDE1200 is capable of self-clocking in the free-standing'RUN' mode, as well as external clocking in the 'STEP' mode. In addition, half-stepping anddirectional control are also available. The TTL-level outputs sequence the stepper drive circuits thatconsist of standard power transistors or a transistor array IC. The EDE1200 features the ability tochange the stepping rate while the motor is stepping and to take an unlimited number of steps incontinuous 'RUN' mode. Inputs are TTL/ CMOS compatible.

RUN mode

In the 'RUN' mode, activated by a low on pin 10, the EDE1200 will cause the motor to rotateaccording to the following parameters:

Direction (pin 7): 1 = clockwise, 0 = counter-clockwise (If a clockwise command causes counterclockwise rotation of motor, reverse the sequence of the motor’s four phase wires.)

Half-Stepping (pin 8): 1 = normal stepping, 0 = half stepping (doubles step resolution)

Speed Control [C,B,A] (pins 13,12,11): these three active-low bits select one of eight rotational speeds. Refer to Tables One & Two below for speed range details.


Table One - Full Step 'RUN' mode speeds*:Revolutions per second & minute are based upon a 1.8 º per step motor.EDE1200 external clock speed is 4 MHz.

Speed Input (C,B,A) RPS RPM000 .152 9.1001 .172 10.3010 .2 12011 .244 14.6100 .303 18.2101 .4 24110 .606 36.4111 1.18 70.6

Table Two - Half-Step 'RUN' mode speeds*:Revolutions per second & minute are based upon a 1.8 º per step motor.EDE1200 external clock speed is 4 MHz.

Speed Input (C,B,A) RPS RPM000 .077 4.6001 .089 5.3010 .103 6.2011 .121 7.27100 .154 9.2101 .2 12110 .303 18.2111 .606 36.4

* NOTE: indicated speeds are approximate and may vary with oscillator frequency and other factors.Please verify exact value before using in any speed-critical application.

The following chart depicts revolutions per second for a 1.8 º stepper motor in relation to the threespeed selection bits for both full and half stepping. Please note that the speed increase is nonlinear;i.e. finer speed control is available at slower step speeds. Again, indicated speeds are approximateand may vary with oscillator frequency. Please verify exact value before using in any speed-criticalapplication.


Motor Speed vs. Speed Selection Bits

1.18

0.3030.3030.4

0.152 0.172 0.20.244

0.6060.606

0.20.1540.1210.1030.0890.077

0

0.2

0.4

0.6

0.8

1

1.2

0 1 2 3 4 5 6 7

Speed Select Input

RPS

RPS, FullRPS, Half

STEP mode

In the 'STEP' mode, an external clock signal is required for each step of the motor. The RUN (pin10) line must be left high. Each low-going pulse on the STEP (pin 9) line causes a movement of the

motor according to the Direction and Half-step pins as specified below:

Direction (pin 7): 1 = clockwise, 0 = counter-clockwise (If a clockwise command causes counterclockwise rotation of motor, reverse the sequence of the motor’s four phase wires.)

Half-Stepping (pin 8): 1 = normal stepping, 0 = half stepping (doubles step resolution)

With the EDE1200 running at an external clock speed of 4 MHz, the 'STEP' pin may be driven atspeeds up to 5 KHz, resulting in a motor speed over 1,500 RPM with a 1.8 º per step motor . Allstepper motors require ramped acceleration to such high RPM rates; do not instantly apply highspeed step requests immediately to a stopped motor. Motor type and load will determine maximumacceleration rate. However, ordinary speed ranges (such as the EDE1200’s ‘RUN’ mode speeds) donot require a ramped acceleration.

Free-Spin

Holding the free-spin input (pin 6) low causes the EDE1200 to de-activate all motor coils. Duringordinary operation (step and run modes) the motor is held in position by the ‘braking’ effect inherentin all stepper motors. Activating this active-low input allows the motor spindle to spin freely withoutthe braking effect. Braking effect is resumed when free-spin input (pin 6) is raised.


Application Examples

Basic Usage Diagram (without power & oscillator connections)

Interfacing to a Microprocessor/ Microcontroller

Free Running Mode Example Setup


Hookup Diagrams

Implementation via Four MJE3055 Transistors

Implementation via ULN2003A IC


ABSOLUTE MAXIMUM RATINGS

Oscillator frequency ......................................... 4 MHzSupply Voltage ................................................. 7.5V

Ambient temperature under bias ...................... -55°C to +125°CMax. current into input pin ............................... ±500µAMax. current sunk by output pin ........................25mAMax. current sourced by output pin .................. 20mAMax. current sourced by all 4 outputs................ 50mAMax. current sunk by all four outputs................. 50mA

STANDARD OPERATING CONDITIONS

Supply voltage ................................................. 3.0V to 5.5VOperating temperature ..................................... 0°C to +70°C

IMPORTANT NOTICE

E-LAB Digital Engineering, Inc. (E-LAB), reserves the rightto change products or specifications without notice.Customers are advised to obtain the latest versions ofproduct specifications, which should be consideredwhen evaluating a product’s appropriateness for aparticular use.

THIS PRODUCT IS WARRANTED TO COMPLY WITHE-LAB’S SPECIFICATION SHEET AT THE TIME OFDELIVERY. BY USING THIS PRODUCT, CUSTOMERAGREES THAT IN NO EVENT SHALL E-LAB BE LIABLEFOR ANY DIRECT, INDIRECT, SPECIAL, INCIDENTALOR CONSEQUENTIAL DAMAGES AS A RESULT OFTHE PERFORMANCE, OR FAILURE TO PERFORM, OFTHIS PRODUCT.

E-LAB MAKES NO OTHER WARRANTIES, EXPRESSEDOR IMPLIED, INCLUDING ANY IMPLIEDWARRANTIES OF MERCHANTABILITY OR FITNESSFOR A PARTICULAR PURPOSE.

E-LAB’s LIABILITY IS FOR A PERIOD NO GREATERTHAN 90 DAYS FROM DATE OF SHIPMENT BY E-LABAND IS LIMITED TO REPLACEMENT OF DEFECTIVEPRODUCT. This warranty covers only defects arisingunder normal use and not malfunctions resulting frommisuse, abuse, modification, or repairs by anyone otherthan E-LAB.

E-LAB’S PRODUCTS ARE NOT AUTHORIZED FOR USEAS CRITICAL COMPONENTS IN LIFE SUPPORTDEVICES OR SYSTEMS WITHOUT THE EXPRESSWRITTEN APPROVAL OF THE PRESIDENT OF E-LAB.Life support devices or systems are those which areintended to support or sustain life and whose failure toperform can be reasonably expected to result in asignificant injury or death to the user. Criticalcomponents are those whose failure to perform can bereasonably expected to cause failure of a life supportdevice or system or affect its safety or effectiveness.

COPYRIGHT NOTICE

This product may not be duplicated. E-LAB Digital Engineering, Inc. holds all copyrights on firmware, with all rightsreserved. Unauthorized duplication of this device may be subject to penalty under state and/ or federal law.

EDE1200 and the E-LAB logo are trademarks of E-LAB Digital Engineering, Inc.

CONTACTING US

E-LAB Digital Engineering, Inc.Carefree Industrial Park1600 N. State Rte. 291 Hwy. Ste. 330Independence, MO 64052-0436

Telephone: (816) 257-9954FAX: (816) 257-9945

www.elabinc.com [email protected]

Stepper Motor

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